.TH std::all_of,std::any_of,std::none_of 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::all_of,std::any_of,std::none_of \- std::all_of,std::any_of,std::none_of

.SH Synopsis
   Defined in header <algorithm>
   template< class InputIt, class UnaryPred >               \fB(1)\fP \fI(since C++11)\fP
   bool all_of( InputIt first, InputIt last, UnaryPred p );     (constexpr since C++20)
   template< class ExecutionPolicy, class ForwardIt, class
   UnaryPred >

   bool all_of( ExecutionPolicy&& policy,                   \fB(2)\fP \fI(since C++17)\fP

                ForwardIt first, ForwardIt last, UnaryPred
   p );
   template< class InputIt, class UnaryPred >               \fB(3)\fP \fI(since C++11)\fP
   bool any_of( InputIt first, InputIt last, UnaryPred p );     (constexpr since C++20)
   template< class ExecutionPolicy, class ForwardIt, class
   UnaryPred >

   bool any_of( ExecutionPolicy&& policy,                   \fB(4)\fP \fI(since C++17)\fP

                ForwardIt first, ForwardIt last, UnaryPred
   p );
   template< class InputIt, class UnaryPred >                   \fI(since C++11)\fP
   bool none_of( InputIt first, InputIt last, UnaryPred p   \fB(5)\fP (constexpr since C++20)
   );
   template< class ExecutionPolicy, class ForwardIt, class
   UnaryPred >

   bool none_of( ExecutionPolicy&& policy,                  \fB(6)\fP \fI(since C++17)\fP

                 ForwardIt first, ForwardIt last, UnaryPred
   p );

   1) Checks if unary predicate p returns true for all elements in the range
   [first, last).
   3) Checks if unary predicate p returns true for at least one element in the range
   [first, last).
   5) Checks if unary predicate p returns true for no elements in the range
   [first, last).
   2,4,6) Same as (1,3,5), but executed according to policy.
   These overloads participate in overload resolution only if

   std::is_execution_policy_v<std::decay_t<ExecutionPolicy>> is true.        (until
                                                                             C++20)
   std::is_execution_policy_v<std::remove_cvref_t<ExecutionPolicy>> is true. (since
                                                                             C++20)

.SH Parameters

   first, last - the range of elements to examine
   policy      - the execution policy to use. See execution policy for details.
                 unary predicate .

                 The expression p(v) must be convertible to bool for every argument v
   p           - of type (possibly const) VT, where VT is the value type of InputIt,
                 regardless of value category, and must not modify v. Thus, a parameter
                 type of VT&is not allowed
                 , nor is VT unless for VT a move is equivalent to a copy
                 \fI(since C++11)\fP.
.SH Type requirements
   -
   InputIt must meet the requirements of LegacyInputIterator.
   -
   ForwardIt must meet the requirements of LegacyForwardIterator.
   -
   UnaryPred must meet the requirements of Predicate.

.SH Return value

                Has true element           Yes                 No
                Has false element     Yes       No        Yes       No
               all_of              false     true      false     true
               any_of              true      true        false     false
               none_of               false     false   true      true

.SH Complexity

   1-6) At most std::distance(first, last) applications of the predicate p.

.SH Exceptions

   The overloads with a template parameter named ExecutionPolicy report errors as
   follows:

     * If execution of a function invoked as part of the algorithm throws an exception
       and ExecutionPolicy is one of the standard policies, std::terminate is called.
       For any other ExecutionPolicy, the behavior is implementation-defined.
     * If the algorithm fails to allocate memory, std::bad_alloc is thrown.

.SH Possible implementation

   See also the implementations of

     * all_of in libstdc++ and libc++.
     * any_of in libstdc++ and libc++.
     * none_of in libstdc++ and libc++.

                                all_of
   template<class InputIt, class UnaryPred>
   constexpr bool all_of(InputIt first, InputIt last, UnaryPred p)
   {
       return std::find_if_not(first, last, p) == last;
   }
                                any_of
   template<class InputIt, class UnaryPred>
   constexpr bool any_of(InputIt first, InputIt last, UnaryPred p)
   {
       return std::find_if(first, last, p) != last;
   }
                               none_of
   template<class InputIt, class UnaryPred>
   constexpr bool none_of(InputIt first, InputIt last, UnaryPred p)
   {
       return std::find_if(first, last, p) == last;
   }

.SH Example


// Run this code

 #include <algorithm>
 #include <functional>
 #include <iostream>
 #include <iterator>
 #include <numeric>
 #include <vector>

 int main()
 {
     std::vector<int> v(10, 2);
     std::partial_sum(v.cbegin(), v.cend(), v.begin());
     std::cout << "Among the numbers: ";
     std::copy(v.cbegin(), v.cend(), std::ostream_iterator<int>(std::cout, " "));
     std::cout << '\\n';

     if (std::all_of(v.cbegin(), v.cend(), [](int i) { return i % 2 == 0; }))
         std::cout << "All numbers are even\\n";

     if (std::none_of(v.cbegin(), v.cend(), std::bind(std::modulus<>(),
                                                      std::placeholders::_1, 2)))
         std::cout << "None of them are odd\\n";

     struct DivisibleBy
     {
         const int d;
         DivisibleBy(int n) : d(n) {}
         bool operator()(int n) const { return n % d == 0; }
     };

     if (std::any_of(v.cbegin(), v.cend(), DivisibleBy(7)))
         std::cout << "At least one number is divisible by 7\\n";
 }

.SH Output:

 Among the numbers: 2 4 6 8 10 12 14 16 18 20
 All numbers are even
 None of them are odd
 At least one number is divisible by 7

.SH See also

   ranges::all_of
   ranges::any_of  checks if a predicate is true for all, any or none of the elements
   ranges::none_of in a range
   (C++20)         (niebloid)
   (C++20)
   (C++20)
